1. Field of the Invention
The present invention relates to a laser welding structure in which a wire and a conductive metal plate are joined together by locally applying a laser beam and thereby melting and solidifying the wire and the conductive metal plate.
2. Description of Related Art
As shown in FIG. 7 of the present application, Japanese Patent Application Publication No. 8-8028 (hereinafter referred to as “Patent literature 1”) discloses a technique to laser-weld a wire 103 to a conductive metal plate 101, which is integrally formed with a terminal 100, by applying a welding-mode laser beam 102 to the conductive metal plate 101.
However, in the technique disclosed in Patent literature 1, though depending on the material, the size, or the combination thereof of the objects to be welded, it is necessary to adjust the total thermal energy to a larger value than necessary to allow for a margin so that the wire 103 as well as the conductive metal plate 101 are melted without fail.
An object of the present invention is to provide a technique to reduce the total thermal energy necessary to melt both the conductive metal plate and the wire.